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-rw-r--r--crypto/geniv.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/crypto/geniv.c b/crypto/geniv.c
new file mode 100644
index 0000000000..bee4621b4f
--- /dev/null
+++ b/crypto/geniv.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * geniv: Shared IV generator code
+ *
+ * This file provides common code to IV generators such as seqiv.
+ *
+ * Copyright (c) 2007-2019 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <crypto/internal/geniv.h>
+#include <crypto/internal/rng.h>
+#include <crypto/null.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+
+static int aead_geniv_setkey(struct crypto_aead *tfm,
+ const u8 *key, unsigned int keylen)
+{
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
+
+ return crypto_aead_setkey(ctx->child, key, keylen);
+}
+
+static int aead_geniv_setauthsize(struct crypto_aead *tfm,
+ unsigned int authsize)
+{
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
+
+ return crypto_aead_setauthsize(ctx->child, authsize);
+}
+
+static void aead_geniv_free(struct aead_instance *inst)
+{
+ crypto_drop_aead(aead_instance_ctx(inst));
+ kfree(inst);
+}
+
+struct aead_instance *aead_geniv_alloc(struct crypto_template *tmpl,
+ struct rtattr **tb)
+{
+ struct crypto_aead_spawn *spawn;
+ struct aead_instance *inst;
+ struct aead_alg *alg;
+ unsigned int ivsize;
+ unsigned int maxauthsize;
+ u32 mask;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+ if (err)
+ return ERR_PTR(err);
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+ if (!inst)
+ return ERR_PTR(-ENOMEM);
+
+ spawn = aead_instance_ctx(inst);
+
+ err = crypto_grab_aead(spawn, aead_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+
+ alg = crypto_spawn_aead_alg(spawn);
+
+ ivsize = crypto_aead_alg_ivsize(alg);
+ maxauthsize = crypto_aead_alg_maxauthsize(alg);
+
+ err = -EINVAL;
+ if (ivsize < sizeof(u64))
+ goto err_free_inst;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "%s(%s)", tmpl->name, alg->base.cra_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+ if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "%s(%s)", tmpl->name, alg->base.cra_driver_name) >=
+ CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = alg->base.cra_priority;
+ inst->alg.base.cra_blocksize = alg->base.cra_blocksize;
+ inst->alg.base.cra_alignmask = alg->base.cra_alignmask;
+ inst->alg.base.cra_ctxsize = sizeof(struct aead_geniv_ctx);
+
+ inst->alg.setkey = aead_geniv_setkey;
+ inst->alg.setauthsize = aead_geniv_setauthsize;
+
+ inst->alg.ivsize = ivsize;
+ inst->alg.maxauthsize = maxauthsize;
+
+ inst->free = aead_geniv_free;
+
+out:
+ return inst;
+
+err_free_inst:
+ aead_geniv_free(inst);
+ inst = ERR_PTR(err);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(aead_geniv_alloc);
+
+int aead_init_geniv(struct crypto_aead *aead)
+{
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(aead);
+ struct aead_instance *inst = aead_alg_instance(aead);
+ struct crypto_aead *child;
+ int err;
+
+ spin_lock_init(&ctx->lock);
+
+ err = crypto_get_default_rng();
+ if (err)
+ goto out;
+
+ err = crypto_rng_get_bytes(crypto_default_rng, ctx->salt,
+ crypto_aead_ivsize(aead));
+ crypto_put_default_rng();
+ if (err)
+ goto out;
+
+ ctx->sknull = crypto_get_default_null_skcipher();
+ err = PTR_ERR(ctx->sknull);
+ if (IS_ERR(ctx->sknull))
+ goto out;
+
+ child = crypto_spawn_aead(aead_instance_ctx(inst));
+ err = PTR_ERR(child);
+ if (IS_ERR(child))
+ goto drop_null;
+
+ ctx->child = child;
+ crypto_aead_set_reqsize(aead, crypto_aead_reqsize(child) +
+ sizeof(struct aead_request));
+
+ err = 0;
+
+out:
+ return err;
+
+drop_null:
+ crypto_put_default_null_skcipher();
+ goto out;
+}
+EXPORT_SYMBOL_GPL(aead_init_geniv);
+
+void aead_exit_geniv(struct crypto_aead *tfm)
+{
+ struct aead_geniv_ctx *ctx = crypto_aead_ctx(tfm);
+
+ crypto_free_aead(ctx->child);
+ crypto_put_default_null_skcipher();
+}
+EXPORT_SYMBOL_GPL(aead_exit_geniv);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Shared IV generator code");